Method for Forming Auxiliary Conductive Unit on Transparent Electrode of Touch Sensor and Product Thereof

1. A method for forming an auxiliary conductive unit on a transparent electrode of a touch sensor, comprising the steps of: a) preparing a conductive substrate: superposing a first touch conductive layer and a first auxiliary conductive layer on a first side of a dielectric substrate in order, superposing a second touch conductive layer and a second auxiliary conductive layer on a second side of the dielectric substrate in order, wherein the first side and the second side are two opposite sides of the dielectric substrate, the first and second touch conductive layers are two transparent conductive films made of an identical material, the first and second auxiliary conductive layers are two opaque conductive films made of an identical material, the first auxiliary conductive layer is less than the first touch conductive layer in sheet resistance, the first auxiliary conductive layer is electrically superposed on the first touch conductive layer, the second auxiliary conductive layer is less than the second touch conductive layer in sheet resistance, and the second auxiliary conductive layer is electrically superposed on the second touch conductive layer; b) performing a first lithography process: forming a first photoresist layer on the first side of the dielectric substrate, forming a first photoresist trail pattern on the first photoresist layer by development, the first photoresist trail pattern comprising a pattern portion of first touch sensing electrodes and a pattern portion of first signal wires, wherein the first touch sensing electrodes are arranged along a first direction and connected in series, and each of the first signal wires electrically connects with one of the first touch sensing electrodes; c) performing a second lithography process: forming a second photoresist layer on the second side of the dielectric substrate, forming a second photoresist trail pattern on the second photoresist layer by development, the second photoresist trail pattern comprising a pattern portion of a second touch sensing electrode and a pattern portion of a second signal wire, wherein the second touch sensing electrodes are arranged along a second direction and connected in series, and the second signal wire electrically connects with the second touch sensing electrode; d) performing a first etching process: etching the first touch conductive layer, the first auxiliary conductive layer, the second touch conductive layer and the second auxiliary conductive layer by using a first etchant to remove portions of material, which are not protected by both the first photoresist layer and the second photoresist layer; e) performing a first stripping process: removing the first and second photoresist layers, forming a first touch conductive trail pattern corresponding to the first photoresist trail pattern on both the first touch conductive layer and the first auxiliary conductive layer on the first side of the dielectric substrate by etching, and forming a second touch conductive trail pattern corresponding to the second photoresist trail pattern on both the second touch conductive layer and the second auxiliary conductive layer on the second side of the dielectric substrate by etching; f) performing a third lithography process: forming a third photoresist layer on the first side of the dielectric substrate, forming a third photoresist trail pattern on the third photoresist layer by development, the third photoresist trail pattern comprising a pattern portion of a first micro auxiliary conductive unit and a pattern portion of a first auxiliary signal wire, wherein the first micro auxiliary conductive unit is disposed in an area range of the first touch sensing electrode, and at least part of the first auxiliary signal wire is overlappingly formed in an area range of the first signal wire; g) performing a fourth lithography process: forming a fourth photoresist layer on the second side of the dielectric substrate, forming a fourth photoresist trail pattern on the fourth photoresist layer by development, the fourth photoresist trail pattern comprising a pattern portion of a second micro auxiliary conductive unit and a pattern portion of a second auxiliary signal wire, wherein the second micro auxiliary conductive unit is disposed in an area range of the second touch sensing electrode, and at least part of the second auxiliary signal wire is overlappingly formed in an area range of the second signal wire; h) performing a second etching process: etching both the first auxiliary conductive layer and the second auxiliary conductive layer by using a second etchant to remove portions of material, which are not protected by both the third photoresist layer and the fourth photoresist layer, wherein the second etchant does not create an etching reaction with materials of both the first touch conductive layer and the second touch conductive layer; and i) performing a second stripping process: removing the third and fourth photoresist layers, forming a first auxiliary conductive trail pattern corresponding to the third photoresist trail pattern on the first auxiliary conductive layer on the first side of the dielectric substrate by etching, the first touch conductive trail pattern is kept on the first touch conductive layer, forming a second auxiliary conductive trail pattern corresponding to the fourth photoresist trail pattern on the second auxiliary conductive layer on the second side of the dielectric substrate by etching, the second touch conductive trail pattern is kept on the second touch conductive layer, wherein the first touch conductive trail pattern, the first auxiliary conductive trail pattern, the second touch conductive trail pattern and the second auxiliary conductive trail pattern jointly constitute a touch sensor.

2. The method of claim 1 , wherein a sheet resistance of each of the first touch conductive layer and the second touch conductive layer is between 80 and 150 ohm/sq, and a sheet resistance of each of the first auxiliary conductive layer and the second auxiliary conductive layer is between 0.05 and 0.2 ohm/sq.

3. The method of claim 1 , wherein the first touch conductive layer and the second touch conductive layer are made of indium tin oxide, indium zinc oxide, zinc aluminum oxide, tin antimony oxide, or polyethylene dioxythiophene.

4. The method of claim 1 , wherein the first auxiliary conductive layer and the second auxiliary conductive layer are made of gold, silver, copper, aluminum, molybdenum, nickel or an alloy thereof.

5. The method of claim 1 , wherein the first etchant is a complex etchant for etching the first touch conductive layer, the second touch conductive layer, the first auxiliary conductive layer and the second auxiliary conductive layer.

6. The method of claim 1 , wherein both the first touch conductive layer and the second touch conductive layer are formed by indium tin oxide, and both the first auxiliary conductive layer and the second auxiliary conductive layer are formed by copper.

7. The method of claim 6 , wherein the first etchant comprises iron nitrate and hydrochloric acid, and the second etchant is iron nitrate.

8. The method of claim 1 , wherein both forming the first photoresist trail pattern on the first photoresist layer and forming the second photoresist trail pattern on the second photoresist layer are implemented simultaneously.

9. The method of claim 1 , wherein both forming the third photoresist trail pattern on the third photoresist layer and forming the fourth photoresist trail pattern on the fourth photoresist layer are implemented simultaneously.

10. A method for forming an auxiliary conductive unit on a transparent electrode of multiple touch sensors, comprising the steps of: a) preparing a conductive substrate: superposing a first touch conductive layer and a first auxiliary conductive layer on a first side of a dielectric substrate in order, superposing a second touch conductive layer and a second auxiliary conductive layer on a second side of the dielectric substrate in order, wherein the first side and the second side are two opposite sides of the dielectric substrate, the first and second touch conductive layers are two transparent conductive films made of an identical material, the first and second auxiliary conductive layers are two opaque conductive films made of an identical material, the first auxiliary conductive layer is less than the first touch conductive layer in sheet resistance, the first auxiliary conductive layer is electrically superposed on the first touch conductive layer, the second auxiliary conductive layer is less than the second touch conductive layer in sheet resistance, and the second auxiliary conductive layer is electrically superposed on the second touch conductive layer; b) performing a first lithography process: forming a first photoresist layer on the first side of the dielectric substrate, forming a first photoresist trail pattern on the first photoresist layer by development, the first photoresist trail pattern comprising a pattern portion of first touch sensing electrodes, a pattern portion of second touch sensing electrodes and a pattern portion of first signal wires, wherein each of the first touch sensing electrodes and the second touch sensing electrodes are arranged parallelly along a first direction at intervals and connected in series, and both at least one end of each of the first touch sensing electrodes and at least one end of each of the second touch sensing electrodes electrically connect with one of the first signal wires; c) performing a second lithography process: forming a second photoresist layer on the second side of the dielectric substrate, forming a second photoresist trail pattern on the second photoresist layer by development, the second photoresist trail pattern comprising a pattern portion of third touch sensing electrodes, a pattern portion of fourth touch sensing electrodes and a pattern portion of second signal wires, wherein each of the third touch sensing electrodes and the fourth touch sensing electrodes are arranged parallelly along a first direction at intervals and connected in series, and both at least one end of each of the third touch sensing electrodes and at least one end of each of the fourth touch sensing electrodes electrically connect with one of the second signal wires; d) performing a first etching process: etching the first touch conductive layer, the first auxiliary conductive layer, the second touch conductive layer and the second auxiliary conductive layer by using a first etchant to remove portions of material, which are not protected by both the first photoresist layer and the second photoresist layer; e) performing a first stripping process: removing the first and second photoresist layers, forming a first touch conductive trail pattern corresponding to the first photoresist trail pattern on both the first touch conductive layer and the first auxiliary conductive layer on the first side of the dielectric substrate by etching, and forming a second touch conductive trail pattern corresponding to the second photoresist trail pattern on both the second touch conductive layer and the second auxiliary conductive layer on the second side of the dielectric substrate by etching; f) performing a third lithography process: forming a third photoresist layer on the first side of the dielectric substrate, forming a third photoresist trail pattern on the third photoresist layer by development, the third photoresist trail pattern comprising a pattern portion of first micro auxiliary conductive units and a pattern portion of first auxiliary signal wires, wherein the first micro auxiliary conductive units are disposed in an area range of the first and second touch sensing electrodes, and at least part of the first auxiliary signal wires is overlappingly formed in an area range of the first signal wires; g) performing a fourth lithography process: forming a fourth photoresist layer on the second side of the dielectric substrate, forming a fourth photoresist trail pattern on the fourth photoresist layer by development, the fourth photoresist trail pattern comprising a pattern portion of second micro auxiliary conductive units and a pattern portion of second auxiliary signal wires, wherein the second micro auxiliary conductive units are disposed in an area range of the third and fourth touch sensing electrodes, and at least part of the second auxiliary signal wires is overlappingly formed in an area range of the second signal wires; h) performing a second etching process: etching both the first auxiliary conductive layer and the second auxiliary conductive layer by using a second etchant to remove portions of material, which are not protected by both the third photoresist layer and the fourth photoresist layer, wherein the second etchant does not create an etching reaction with materials of both the first touch conductive layer and the second touch conductive layer; and i) performing a second stripping process: removing the third and fourth photoresist layers, forming a first auxiliary conductive trail pattern corresponding to the third photoresist trail pattern on the first auxiliary conductive layer on the first side of the dielectric substrate by etching, the first touch conductive trail pattern is kept on the first touch conductive layer, forming a second auxiliary conductive trail pattern corresponding to the fourth photoresist trail pattern on the second auxiliary conductive layer on the second side of the dielectric substrate by etching, the second touch conductive trail pattern is kept on the second touch conductive layer, wherein the first touch conductive trail pattern, the first auxiliary conductive trail pattern, the second touch conductive trail pattern and the second auxiliary conductive trail pattern jointly constitute at least two touch sensors.

11. The method of claim 10 , wherein a sheet resistance of each of the first touch conductive layer and the second touch conductive layer is between 80 and 150 ohm/sq, and a sheet resistance of each of the first auxiliary conductive layer and the second auxiliary conductive layer is between 0.05 and 0.2 ohm/sq.

12. The method of claim 10 , wherein the first touch conductive layer and the second touch conductive layer are made of indium tin oxide, indium zinc oxide, zinc aluminum oxide, tin antimony oxide, or polyethylene dioxythiophene.

13. The method of claim 10 , wherein the first auxiliary conductive layer and the second auxiliary conductive layer are made of gold, silver, copper, aluminum, molybdenum, nickel or an alloy thereof.

14. The method of claim 10 , wherein the first etchant is a complex etchant for etching the first touch conductive layer, the second touch conductive layer, the first auxiliary conductive layer and the second auxiliary conductive layer.

15. The method of claim 10 , wherein both the first touch conductive layer and the second touch conductive layer are formed by indium tin oxide, and both the first auxiliary conductive layer and the second auxiliary conductive layer are formed by copper.

16. The method of claim 15 , wherein the first etchant comprises iron nitrate and hydrochloric acid, and the second etchant is iron nitrate.

17. The method of claim 10 , wherein both forming the first photoresist trail pattern on the first photoresist layer and forming the second photoresist trail pattern on the second photoresist layer are implemented simultaneously.

18. The method of claim 10 , wherein both forming the third photoresist trail pattern on the third photoresist layer and forming the fourth photoresist trail pattern on the fourth photoresist layer are implemented simultaneously.

19. The method of claim 10 , wherein both the first touch sensing electrodes and the first micro auxiliary conductive units jointly constitute a first directional capacitive touch sensing electrodes, both the third touch sensing electrodes and the second micro auxiliary conductive units jointly constitute a second directional capacitive touch sensing electrodes, and both the first directional capacitive touch sensing electrodes and the second directional capacitive touch sensing electrodes jointly constitute a capacitive touch sensor.

20. The method of claim 10 , wherein both the second touch sensing electrodes and the first micro auxiliary conductive units jointly constitute a first directional electromagnetic touch sensing electrodes, both the fourth touch sensing electrodes and the second micro auxiliary conductive units jointly constitute a second directional electromagnetic touch sensing electrodes, and both the first directional electromagnetic touch sensing electrodes and the second directional electromagnetic touch sensing electrodes jointly constitute an electromagnetic touch sensor.